Lubricating oil



Patented pr. `20, 1943 STATS TNT LUmoA'nNd on.

Frederic A. Armiield, Berkeley, Calif., assignor to Shell Development Company, San Francisco,

Calif., a corporation of Delaware Application August 30, .1941,y Serial No. 409,066

8 Claims.

This invention relatesl to the production of new and useful lubricating and electrical oils from suitable hydrocarbon oils by the incorporation of a minor amount of a combination of oilsoluble improving agents.

The invention pertains to a method for the stabilization of hydrocarbon oils and particularly to their protection against deterioration by oxidation which is catatheir compounds which may be contained in the sludges.

H ydrocarbon oils normally contact metals and after some period of use frequently contain small -amounts of metals, usually associated with sludge, either dissolved in the form of a soluble salt or dispersed in the form of the free metal or an insoluble compound. It has been observed that the presence of such sludges f1 equently has a detrimental effect on the stability of the hydrocaribon oil. inasmuch as bare traces of the metals or metal compounds may be very harmful, and since their removal is quite difficult and even if successful would be quickly nulliiiedV by the formation of new traces, itis often not practical to eliminate this troublesome catalyst for oxidation reaction. 'Ihis is true in engines, especially internal combustion engines wherein metal catalysts always tend to become dispersed through wear, corrosion, oxidation, etc.

It has alreadybeen suggested to reduce the susceptibility of organic substances to oxidation induced by the presence of certain metals by adding to the organic substance certain deactivators which have the property of rendering the metal inactive. A typical deactivator destroys the eiectiveness of the catalyst in theerties are for example, oil-soluble heterocyclic nitrogen compounds such as carboxy pyridines, hydroxy pyridines, pyridines having a plurality of acidic radicals, corresponding compounds of oxidation proceeds unitin-- pyridine, etc.; reaction products :gli diacylcompounds and primary amines 'suchv as d ibenzoyl acetonyl ethylenediamine, vdiacetyl ac etonyl ethylene diamine; reaction products of an aromatic ortho-hydroxy aldehyde or ketone with alkylamines or hydroxy alkylamines'f such'as salicylal ethylamine, salicylal ethanol'amine, N salicylal N ethanol diamine, disalicylal ethylene diamine; disalicylal triethylenetetramine. di- (2 hydroxy 3 methoxybenzal) propylene diamine, di (2 hydroxy 5;- chlorobenzal) boxybenzal) -ethylene diamine, etc.: hydroxy aromatic aldoximes and ketox ime s siirulrjlti- "hydroxy-naphthylaldoxime, 2-hydrxy-benza doxime, 2-hydroxy-acetophenoxime, etc. I l.

However, it has been observed that, in general deactivators have a markedlyl reducedeieci quinoline, is'oquinoline, acridine, phenanthridine,

phenazine, quinoxaline, quinazoline, anthrawhen added to oils containing sludge or which quickly develop sludge during use. The instant invention involves the discovers that the action of metal deactivators i'n pils taining or developing sludge during's'eis enhanced b'y the presence of phosphat'idessuch as lecithin. For example, addition of 1/2f% o1 lecithin to an oil containing 1/2% of 'aq'etaldeactivator such as N salicylal N ethanol" diaiinf stabilizes the oil and effectively inhibits sludge formation and catalyticl oxidationto agreatei extent than is obtainable with either 1%y o1 lecithin or 1% of N salicylal N"l ethanol diamine alone.

Although lecithin is preferred for use in accordance with this invention, it is possible to use cephalin and other' natural phosphatides of plant or animal origin as, for example; are* found in substantial quantities in soybeans, 4or synthetic In either case, the useful Ip'r-'oductf onor on OZ where X and Y are fatty acyl radicals' derived from stearic, palmitic, oleic acids, etc., andwher Z represents an amino alcohol group. inthe case of lecithin the' amino alcohol group it choune-,omcmmcmnon l l l The amounts of deactivators andfiihsphatidea which may be added may "varybet'venwldi limits depending upon specic coditionsgtbs met. The amounts of metal'dectivatorddec to lubricating oils may be as lowas .001%"b1 of the individual effects.

The combination of ingredients of this invencombination of the individual components, respectively.

It will be seen that the metallic iron was deac tivated by thecombination for a considerably longer time thanpcould be expected from the sum y tion may be used in conjunction with other addi- :ight of the phosphatide, although amounts up v3% may be utilized, depending upon the stality requirements. Metal deactivators and phosphatides used in counts necessary to impart stability to my hyyocarbon oil compositions give the best results rien employed within a preferred range of rela.- le amounts. Thus it is desirable that the range ratios Vary from iive parts of phosphatide to 1e part of deactivator to approximately ten parts phosphatide to one part of deactivator. leferred ratio of the lcompounding ingredients based on the relative amounts of the two inyedients, irrespective^of the total amounts, as scussed hereinbefore, which may be present in e liquid or of other addition agents which may apresent. In the following example, the beneficial effect one particular vcombination of compounds is ustrated. A sample ofl lubricating oil grade A. E. 30 was divided into four portions.' `To .ch sample was added 3.5 cm. of iron/surface n. of oil in the form of iron wire. To the rst )rtion was added 1% by weight of lecithin. To Le second portion was added .1% by weight of salicylal N' ethanol diamine. To the third )rtion w added the combination 1% by weight lecithin and .1% of N salicylal N' ethanol dinine. The uncompounded and compounded .mples were tested by exposing the oils to pure :ygen at atmospheric pressure and at a tem- 'I'his tion agents, for example, in lubricating oils together with anti-oxidants, blooming agents, anticorrosives, extreme pressure compounds, detergents, etc.

I claim as my invention: 'y

1. The method of inhibiting the catalytic oxidation of a lubricating or electrical oil caused by sludge containing a catalyst of the group consist- .ing'oi' copper, iron, chromium, lead, and their compounds which comprises incorporating in said irature of 150 C. for several hours .whereaiter Y sludge was formed. The effecten oxidation ability of oils of the addition of lecithin to an l containing a deactivator is illustrated by the '.tached drawing representing a graph wherein ie length of time in hours of oxidation is plotted phatide and a metal deactlvator selected from the class consisting of the reaction products of a primaryy amine anda beta carbonyl compound, the latter being selected from the group .consisting vor aliphatic diacyl and 'aromatic o-hydroxy carbonyl compounds.

2. A lubricating composition comprising a reflned mineral lubricating oil: subject to 'sludge formation through activated oxidation caused by the presence of a. member of the group consisting of copper, iron, chromium, lead, and their compounds, and containing small amounts each of a phosphatide and a metal deactivator selected from the class consisting of the reaction products of a primary amine 'and a beta carbonyl compound, the latter 4being selected from the group consisting of aliphatic diacyi and aromatic o-hydroxy carbonyl compounds.

3. The composition of claim 2, whichcontains '.01 to 3.0% by weight of the phosphatide and .001 to 2% of the metal deactivator. 4. The composition of claim 2 which contains .05 to 1.0% by weight of the phosphatide and .0l to .15% of the metal deactivator.

5. 'I'he composition of claim 2 in which the ratio of amounts ofA phosphatide to metal deactivator is between 5 and 10 to 1. l

6. The method of claim 1, wherein the phosphatide is lecithin.

'7. The method of claim 1, wherein the phosphatide is lecithin and the deactivator is` N-salicylal N' ethanol diamine.

8. 'I'he composition of claim 2, wherein the de,-

activator is di-salicylal ethylene diamine.

FREDERIC A. ARMFIELD. 

